Passive spiral galaxies deeply captured by Subaru Hyper Suprime-Cam
Abstract
This paper presents a thousand passive spiral galaxy samples at z = 0.01-0.3 based on a combined analysis of the Third Public Data Release of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP PDR3) and the GALEX-SDSS-WISE Legacy Catalog (GSWLC-2). Among 54871 gri galaxy cutouts taken from the HSC-SSP PDR3 over 1072 deg2, we conducted a search with deep-learning morphological classification for candidates of passive spirals below the star-forming main sequence derived by ultraviolet to mid-infrared spectral energy distribution fitting in the GSWLC-2. We then classified the candidates into 1100 passive spirals and 1141 secondary samples based on visual inspections. Most of the latter cases are considered to be passive ringed S0 or pseudo-ringed galaxies. The remaining secondary samples have ambiguous morphologies, including two peculiar objects with diamond-shaped stellar wings. The selected passive spirals have a similar distribution to the general quiescent galaxies on the EWHδ-Dn4000 diagram and concentration indices. Moreover, we detected an enhanced passive fraction of spiral galaxies in X-ray clusters. Passive spirals in galaxy clusters are preferentially located in the midterm or late infall phase on the phase-space diagram, supporting the ram pressure scenario, which has been widely advocated in previous studies. The source catalog and gri-composite images are available on the HSC-SSP PDR3 website <https://hsc.mtk.nao.ac.jp/ssp/data-release/>. Future updates, including integration with a citizen science project dedicated to the HSC data, will achieve more effective and comprehensive classifications.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- June 2022
- DOI:
- 10.1093/pasj/psac023
- arXiv:
- arXiv:2203.00969
- Bibcode:
- 2022PASJ...74..612S
- Keywords:
-
- galaxies: evolution;
- galaxies: formation;
- galaxies: general;
- galaxies: spiral;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 15 pages, 12 figures. Accepted for publication in Publications of the Astronomical Society of Japan (PASJ). The source catalog and images will be released on the HSC-SSP PDR3 website in March 2022